Thespian memories … Laurence Olivier and architect Denys Lasdun with a model of the proposed National Theatre in 1967. Photograph: Hulton-Deutsch/Corbis

My Sunday mornings are in disarray after the news that Desert Island Discs is on holiday. (What a lovely idea. Where does it go – Mauritius? Or Torquay?)

I'm not too worried, though, because the perfect replacement is stepping in. The Reunion is every bit the equal of Desert Island Discs, another broadcasting gem set in format gold. Sony award-winning host Sue MacGregor brings together people who have been involved in recent events of national importance, and they explain what happened. It's that simple.

The programme is a masterclass in discreet interview techniques, disarming yet probing. MacGregor squeezes out details with a gentle prod rather than a chokehold. "What happened next?" she asks, pausing to add calmly and authoritatively: "And then?" She never interrupts.

The Reunion is always revealing, employing a liberal and creative interpretation of what is relevant – to the extent that some choices might seem odd: for example, the founding of the national lottery is given the same weight as the Tory landslide of 1979. Last season's conversation with the stars and writers of long-running radio comedy The Navy Lark initially seemed incongruous, but it was, as always, a window on a forgotten world.

People who were there candidly share their memories. The benefit of passing years allows space for players who may have been in conflict at the time – who may not even have been on speaking terms, or simply lost touch – to sit around a table again and talk.

The last series included a surprisingly moving encounter between prison officers and prisoners involved in the Salford prison riots. The episode was quite harrowing, as the memories and the mutual sense of injustice were still raw. By contrast, the reunion of actors who starred in Withnail and I was as funny as you'd imagine.

The calibre of guests is always stellar. This Sunday's edition explores the birth of the National Theatre in 1963. An impressive list of British acting aristocracy (no un-gonged thespians allowed) meet again, including Dame Maggie Smith, Dame Joan Plowright, Sir Derek Jacobi and Sir Michael Gambon. So plentiful are the titles that I feel quite inadequate writing this without one. Associate director William "Bill" Gaskill also appears, despite not having been honoured by Her Majesty. Ominously, perhaps, the cast will offer their thoughts on the National Theatre of today. Darling, they'll be marvellous!